/*
 * Copyright (c) 1994, 2004, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 */

package java.io;

/**
 * A data output stream lets an application write primitive Java data
 * types to an output stream in a portable way. An application can
 * then use a data input stream to read the data back in.
 *
 * @author unascribed
 * @see java.io.DataInputStream
 * @since JDK1.0
 */
public class DataOutputStream extends FilterOutputStream implements DataOutput {

  /**
   * The number of bytes written to the data output stream so far.
   * If this counter overflows, it will be wrapped to Integer.MAX_VALUE.
   */
  protected int written;

  /**
   * bytearr is initialized on demand by writeUTF
   */
  private byte[] bytearr = null;

  /**
   * Creates a new data output stream to write data to the specified
   * underlying output stream. The counter <code>written</code> is
   * set to zero.
   *
   * @param out the underlying output stream, to be saved for later use.
   * @see java.io.FilterOutputStream#out
   */
  public DataOutputStream(OutputStream out) {
    super(out);
  }

  /**
   * Increases the written counter by the specified value
   * until it reaches Integer.MAX_VALUE.
   */
  private void incCount(int value) {
    int temp = written + value;
    if (temp < 0) {
      temp = Integer.MAX_VALUE;
    }
    written = temp;
  }

  /**
   * Writes the specified byte (the low eight bits of the argument
   * <code>b</code>) to the underlying output stream. If no exception
   * is thrown, the counter <code>written</code> is incremented by
   * <code>1</code>.
   * <p>
   * Implements the <code>write</code> method of <code>OutputStream</code>.
   *
   * @param b the <code>byte</code> to be written.
   * @throws IOException if an I/O error occurs.
   * @see java.io.FilterOutputStream#out
   */
  public synchronized void write(int b) throws IOException {
    out.write(b);
    incCount(1);
  }

  /**
   * Writes <code>len</code> bytes from the specified byte array
   * starting at offset <code>off</code> to the underlying output stream.
   * If no exception is thrown, the counter <code>written</code> is
   * incremented by <code>len</code>.
   *
   * @param b the data.
   * @param off the start offset in the data.
   * @param len the number of bytes to write.
   * @throws IOException if an I/O error occurs.
   * @see java.io.FilterOutputStream#out
   */
  public synchronized void write(byte b[], int off, int len)
      throws IOException {
    out.write(b, off, len);
    incCount(len);
  }

  /**
   * Flushes this data output stream. This forces any buffered output
   * bytes to be written out to the stream.
   * <p>
   * The <code>flush</code> method of <code>DataOutputStream</code>
   * calls the <code>flush</code> method of its underlying output stream.
   *
   * @throws IOException if an I/O error occurs.
   * @see java.io.FilterOutputStream#out
   * @see java.io.OutputStream#flush()
   */
  public void flush() throws IOException {
    out.flush();
  }

  /**
   * Writes a <code>boolean</code> to the underlying output stream as
   * a 1-byte value. The value <code>true</code> is written out as the
   * value <code>(byte)1</code>; the value <code>false</code> is
   * written out as the value <code>(byte)0</code>. If no exception is
   * thrown, the counter <code>written</code> is incremented by
   * <code>1</code>.
   *
   * @param v a <code>boolean</code> value to be written.
   * @throws IOException if an I/O error occurs.
   * @see java.io.FilterOutputStream#out
   */
  public final void writeBoolean(boolean v) throws IOException {
    out.write(v ? 1 : 0);
    incCount(1);
  }

  /**
   * Writes out a <code>byte</code> to the underlying output stream as
   * a 1-byte value. If no exception is thrown, the counter
   * <code>written</code> is incremented by <code>1</code>.
   *
   * @param v a <code>byte</code> value to be written.
   * @throws IOException if an I/O error occurs.
   * @see java.io.FilterOutputStream#out
   */
  public final void writeByte(int v) throws IOException {
    out.write(v);
    incCount(1);
  }

  /**
   * Writes a <code>short</code> to the underlying output stream as two
   * bytes, high byte first. If no exception is thrown, the counter
   * <code>written</code> is incremented by <code>2</code>.
   *
   * @param v a <code>short</code> to be written.
   * @throws IOException if an I/O error occurs.
   * @see java.io.FilterOutputStream#out
   */
  public final void writeShort(int v) throws IOException {
    out.write((v >>> 8) & 0xFF);
    out.write((v >>> 0) & 0xFF);
    incCount(2);
  }

  /**
   * Writes a <code>char</code> to the underlying output stream as a
   * 2-byte value, high byte first. If no exception is thrown, the
   * counter <code>written</code> is incremented by <code>2</code>.
   *
   * @param v a <code>char</code> value to be written.
   * @throws IOException if an I/O error occurs.
   * @see java.io.FilterOutputStream#out
   */
  public final void writeChar(int v) throws IOException {
    out.write((v >>> 8) & 0xFF);
    out.write((v >>> 0) & 0xFF);
    incCount(2);
  }

  /**
   * Writes an <code>int</code> to the underlying output stream as four
   * bytes, high byte first. If no exception is thrown, the counter
   * <code>written</code> is incremented by <code>4</code>.
   *
   * @param v an <code>int</code> to be written.
   * @throws IOException if an I/O error occurs.
   * @see java.io.FilterOutputStream#out
   */
  public final void writeInt(int v) throws IOException {
    out.write((v >>> 24) & 0xFF);
    out.write((v >>> 16) & 0xFF);
    out.write((v >>> 8) & 0xFF);
    out.write((v >>> 0) & 0xFF);
    incCount(4);
  }

  private byte writeBuffer[] = new byte[8];

  /**
   * Writes a <code>long</code> to the underlying output stream as eight
   * bytes, high byte first. In no exception is thrown, the counter
   * <code>written</code> is incremented by <code>8</code>.
   *
   * @param v a <code>long</code> to be written.
   * @throws IOException if an I/O error occurs.
   * @see java.io.FilterOutputStream#out
   */
  public final void writeLong(long v) throws IOException {
    writeBuffer[0] = (byte) (v >>> 56);
    writeBuffer[1] = (byte) (v >>> 48);
    writeBuffer[2] = (byte) (v >>> 40);
    writeBuffer[3] = (byte) (v >>> 32);
    writeBuffer[4] = (byte) (v >>> 24);
    writeBuffer[5] = (byte) (v >>> 16);
    writeBuffer[6] = (byte) (v >>> 8);
    writeBuffer[7] = (byte) (v >>> 0);
    out.write(writeBuffer, 0, 8);
    incCount(8);
  }

  /**
   * Converts the float argument to an <code>int</code> using the
   * <code>floatToIntBits</code> method in class <code>Float</code>,
   * and then writes that <code>int</code> value to the underlying
   * output stream as a 4-byte quantity, high byte first. If no
   * exception is thrown, the counter <code>written</code> is
   * incremented by <code>4</code>.
   *
   * @param v a <code>float</code> value to be written.
   * @throws IOException if an I/O error occurs.
   * @see java.io.FilterOutputStream#out
   * @see java.lang.Float#floatToIntBits(float)
   */
  public final void writeFloat(float v) throws IOException {
    writeInt(Float.floatToIntBits(v));
  }

  /**
   * Converts the double argument to a <code>long</code> using the
   * <code>doubleToLongBits</code> method in class <code>Double</code>,
   * and then writes that <code>long</code> value to the underlying
   * output stream as an 8-byte quantity, high byte first. If no
   * exception is thrown, the counter <code>written</code> is
   * incremented by <code>8</code>.
   *
   * @param v a <code>double</code> value to be written.
   * @throws IOException if an I/O error occurs.
   * @see java.io.FilterOutputStream#out
   * @see java.lang.Double#doubleToLongBits(double)
   */
  public final void writeDouble(double v) throws IOException {
    writeLong(Double.doubleToLongBits(v));
  }

  /**
   * Writes out the string to the underlying output stream as a
   * sequence of bytes. Each character in the string is written out, in
   * sequence, by discarding its high eight bits. If no exception is
   * thrown, the counter <code>written</code> is incremented by the
   * length of <code>s</code>.
   *
   * @param s a string of bytes to be written.
   * @throws IOException if an I/O error occurs.
   * @see java.io.FilterOutputStream#out
   */
  public final void writeBytes(String s) throws IOException {
    int len = s.length();
    for (int i = 0; i < len; i++) {
      out.write((byte) s.charAt(i));
    }
    incCount(len);
  }

  /**
   * Writes a string to the underlying output stream as a sequence of
   * characters. Each character is written to the data output stream as
   * if by the <code>writeChar</code> method. If no exception is
   * thrown, the counter <code>written</code> is incremented by twice
   * the length of <code>s</code>.
   *
   * @param s a <code>String</code> value to be written.
   * @throws IOException if an I/O error occurs.
   * @see java.io.DataOutputStream#writeChar(int)
   * @see java.io.FilterOutputStream#out
   */
  public final void writeChars(String s) throws IOException {
    int len = s.length();
    for (int i = 0; i < len; i++) {
      int v = s.charAt(i);
      out.write((v >>> 8) & 0xFF);
      out.write((v >>> 0) & 0xFF);
    }
    incCount(len * 2);
  }

  /**
   * Writes a string to the underlying output stream using
   * <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
   * encoding in a machine-independent manner.
   * <p>
   * First, two bytes are written to the output stream as if by the
   * <code>writeShort</code> method giving the number of bytes to
   * follow. This value is the number of bytes actually written out,
   * not the length of the string. Following the length, each character
   * of the string is output, in sequence, using the modified UTF-8 encoding
   * for the character. If no exception is thrown, the counter
   * <code>written</code> is incremented by the total number of
   * bytes written to the output stream. This will be at least two
   * plus the length of <code>str</code>, and at most two plus
   * thrice the length of <code>str</code>.
   *
   * @param str a string to be written.
   * @throws IOException if an I/O error occurs.
   */
  public final void writeUTF(String str) throws IOException {
    writeUTF(str, this);
  }

  /**
   * Writes a string to the specified DataOutput using
   * <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
   * encoding in a machine-independent manner.
   * <p>
   * First, two bytes are written to out as if by the <code>writeShort</code>
   * method giving the number of bytes to follow. This value is the number of
   * bytes actually written out, not the length of the string. Following the
   * length, each character of the string is output, in sequence, using the
   * modified UTF-8 encoding for the character. If no exception is thrown, the
   * counter <code>written</code> is incremented by the total number of
   * bytes written to the output stream. This will be at least two
   * plus the length of <code>str</code>, and at most two plus
   * thrice the length of <code>str</code>.
   *
   * @param str a string to be written.
   * @param out destination to write to
   * @return The number of bytes written out.
   * @throws IOException if an I/O error occurs.
   */
  static int writeUTF(String str, DataOutput out) throws IOException {
    int strlen = str.length();
    int utflen = 0;
    int c, count = 0;

        /* use charAt instead of copying String to char array */
    for (int i = 0; i < strlen; i++) {
      c = str.charAt(i);
      if ((c >= 0x0001) && (c <= 0x007F)) {
        utflen++;
      } else if (c > 0x07FF) {
        utflen += 3;
      } else {
        utflen += 2;
      }
    }

    if (utflen > 65535) {
      throw new UTFDataFormatException(
          "encoded string too long: " + utflen + " bytes");
    }

    byte[] bytearr = null;
    if (out instanceof DataOutputStream) {
      DataOutputStream dos = (DataOutputStream) out;
      if (dos.bytearr == null || (dos.bytearr.length < (utflen + 2))) {
        dos.bytearr = new byte[(utflen * 2) + 2];
      }
      bytearr = dos.bytearr;
    } else {
      bytearr = new byte[utflen + 2];
    }

    bytearr[count++] = (byte) ((utflen >>> 8) & 0xFF);
    bytearr[count++] = (byte) ((utflen >>> 0) & 0xFF);

    int i = 0;
    for (i = 0; i < strlen; i++) {
      c = str.charAt(i);
      if (!((c >= 0x0001) && (c <= 0x007F))) {
        break;
      }
      bytearr[count++] = (byte) c;
    }

    for (; i < strlen; i++) {
      c = str.charAt(i);
      if ((c >= 0x0001) && (c <= 0x007F)) {
        bytearr[count++] = (byte) c;

      } else if (c > 0x07FF) {
        bytearr[count++] = (byte) (0xE0 | ((c >> 12) & 0x0F));
        bytearr[count++] = (byte) (0x80 | ((c >> 6) & 0x3F));
        bytearr[count++] = (byte) (0x80 | ((c >> 0) & 0x3F));
      } else {
        bytearr[count++] = (byte) (0xC0 | ((c >> 6) & 0x1F));
        bytearr[count++] = (byte) (0x80 | ((c >> 0) & 0x3F));
      }
    }
    out.write(bytearr, 0, utflen + 2);
    return utflen + 2;
  }

  /**
   * Returns the current value of the counter <code>written</code>,
   * the number of bytes written to this data output stream so far.
   * If the counter overflows, it will be wrapped to Integer.MAX_VALUE.
   *
   * @return the value of the <code>written</code> field.
   * @see java.io.DataOutputStream#written
   */
  public final int size() {
    return written;
  }
}
